Ranger program

Last updated
Ranger
Ranger 6789.svg
Block III Ranger spacecraft
Manufacturer Jet Propulsion Laboratory
Country of originUnited States
Operator NASA
Specifications
Bus Block I, Block II, Block III
Production
StatusRetired
Launched9
Failed5
Maiden launchAugust 23, 1961
Last launchMarch 21, 1965
Related spacecraft
Derivatives Mariner
Configuration
1964 71395L-Ranger.svg
Block II Ranger spacecraft
First image of the Moon returned by a Ranger mission (Ranger 7 in 1964) Ranger7 PIA02975.jpg
First image of the Moon returned by a Ranger mission (Ranger 7 in 1964)

The Ranger program was a series of uncrewed space missions by the United States in the 1960s whose objective was to obtain the first close-up images of the surface of the Moon. The Ranger spacecraft were designed to take images of the lunar surface, transmitting those images to Earth until the spacecraft were destroyed upon impact. A series of mishaps, however, led to the failure of the first six flights. At one point, the program was called "shoot and hope". [1] Congress launched an investigation into "problems of management" at NASA Headquarters and Jet Propulsion Laboratory. [2] After two reorganizations of the agencies,[ citation needed ] Ranger 7 successfully returned images in July 1964, followed by two more successful missions.

Contents

Ranger was originally designed, beginning in 1959, in three distinct phases, called "blocks". Each block had different mission objectives and progressively more advanced system design. The JPL mission designers planned multiple launches in each block, to maximize the engineering experience and scientific value of the mission and to assure at least one successful flight. Total research, development, launch, and support costs for the Ranger series of spacecraft (Rangers 1 through 9) was approximately $170 million (equivalent to $1.21 billion in 2022). [3]

Ranger spacecraft

Program Ranger Organization Chart Program Ranger organization.jpg
Program Ranger Organization Chart

Each of the block III Ranger spacecraft had six cameras on board. The cameras were fundamentally the same with differences in exposure times, fields of view, lenses, and scan rates. The camera system was divided into two channels, P (partial) and F (full). Each channel was self-contained with separate power supplies, timers, and transmitters. The F-channel had two cameras: the wide-angle A-camera and the narrow angle B-camera. The P-channel had four cameras: P1 and P2 (narrow angle) and P3 and P4 (wide angle). The final F-channel image was taken between 2.5 and 5 seconds before impact (altitude about 5 kilometres (3.1 mi)) and the last P-channel image 0.2 to 0.4 seconds before impact (altitude about 600 metres (2,000 ft)). The images provided better resolution than was available from Earth-based views by a factor of 1000. The design and construction of the cameras was led by Leonard R Malling. [4] [5] [6] [7] The Ranger program manager for the first six spacecraft was James D. Burke. [8]

The camera preamplifiers of the Ranger program used Nuvistors. [9]

Mission list

Block 1 missions

Ranger block I spacecraft diagram. (NASA) Ranger Block 1 scientific experiments.jpg
Ranger block I spacecraft diagram. (NASA)

Block 1, consisting of two spacecraft launched into Earth orbit in 1961, was intended to test the Atlas-Agena launch vehicle and spacecraft equipment without attempting to reach the Moon.

Problems with the early version of the launch vehicle left Ranger 1 and Ranger 2 in short-lived, low-Earth orbits in which the spacecraft could not stabilize themselves, collect solar power, or survive for long. In 1962, JPL utilized the Ranger 1 and Ranger 2 design for the failed Mariner 1 and successful Mariner 2 deep-space probes to Venus.

Block 2 missions

A Ranger probe undergoing restoration at the Udvar-Hazy Center 20180328 Ranger restoration Udvar-Hazy.jpg
A Ranger probe undergoing restoration at the Udvar-Hazy Center

Block 2 of the Ranger project launched three spacecraft to the Moon in 1962, carrying a TV camera, a radiation detector, and a seismometer in a separate capsule slowed by a rocket motor and packaged to survive its low-speed impact on the Moon's surface. The craft weighed 331 kg. The three missions together demonstrated good performance of the Atlas/Agena B launch vehicle and the adequacy of the spacecraft design, but unfortunately not both on the same attempt. Ranger 3 had problems with both the launch vehicle and the spacecraft, missed the Moon by about 36,800 km, and has orbited the Sun ever since. Ranger 4 had a perfect launch, but the spacecraft was completely disabled. The project team tracked the seismometer capsule to impact just out of sight on the lunar far side, validating the communications and navigation system. Ranger 5 missed the Moon and was disabled. No significant science information was gleaned from these missions.

Around the end of Block 2, it was discovered that a type of diode used in previous missions produced problematic gold-plate flaking in the conditions of space. This may have been responsible for some of the failures. [10]

Block 3 missions

Ranger block III spacecraft diagram. (NASA) Ranger 6789.svg
Ranger block III spacecraft diagram. (NASA)

Ranger's Block 3 embodied four launches in 1964-65. These spacecraft boasted a television instrument designed to observe the lunar surface during the approach; as the spacecraft neared the Moon, it would reveal detail smaller than the best Earth telescopes could show, and finally dishpan-sized craters. [11] The first of the new series, Ranger 6, had a flawless flight, except that the television system was disabled by an in-flight accident and could take no pictures.

The next three Rangers, with a redesigned television, were completely successful. Ranger 7 photographed its way down to target in a lunar plain, soon named Mare Cognitum, south of the crater Copernicus. It sent more than 4,300 pictures from six cameras to waiting scientists and engineers. The new images revealed that craters caused by impact were the dominant features of the Moon's surface, even in the seemingly smooth and empty plains. Great craters were marked by small ones, and the small with tiny impact pockmarks, as far down in size as could be discerned—about 50 centimeters (20 inches). The light-colored streaks radiating from Copernicus and a few other large craters turned out to be chains and nets of small craters and debris blasted out in the primary impacts.

In February 1965, Ranger 8 swept an oblique course over the south of Oceanus Procellarum and Mare Nubium, to crash in Mare Tranquillitatis about 70 kilometers (43 mi) distant from where Apollo 11 would land 4½ years later. It garnered more than 7,000 images, covering a wider area and reinforcing the conclusions from Ranger 7. About a month later, Ranger 9 came down in the 90-kilometer (56-mile) diameter crater Alphonsus. Its 5,800 images, nested concentrically and taking advantage of very low-level sunlight, provided strong confirmation of the crater-on-crater, gently rolling contours of the lunar surface.

See also

Related Research Articles

<span class="mw-page-title-main">Jet Propulsion Laboratory</span> Research and development center and NASA field center in California, United States

Jet Propulsion Laboratory (JPL) is a federally funded research and development center in Pasadena, California, United States. Founded in 1936 by Caltech researchers, the laboratory is now owned and sponsored by the National Aeronautics and Space Administration (NASA) and administered and managed by the California Institute of Technology.

<span class="mw-page-title-main">Mariner program</span> NASA space program from 1962 to 1973

The Mariner program was conducted by the American space agency NASA to explore other planets. Between 1962 and late 1973, NASA's Jet Propulsion Laboratory (JPL) designed and built 10 robotic interplanetary probes named Mariner to explore the inner Solar System - visiting the planets Venus, Mars and Mercury for the first time, and returning to Venus and Mars for additional close observations.

<span class="mw-page-title-main">Mariner 1</span> 1962 NASA unmanned mission to fly by Venus

Mariner 1, built to conduct the first American planetary flyby of Venus, was the first spacecraft of NASA's interplanetary Mariner program. Developed by Jet Propulsion Laboratory, and originally planned to be a purpose-built probe launched summer 1962, Mariner 1's design was changed when the Centaur proved unavailable at that early date. Mariner 1, were then adapted from the lighter Ranger lunar spacecraft. Mariner 1 carried a suite of experiments to determine the temperature of Venus as well to measure magnetic fields and charged particles near the planet and in interplanetary space.

<span class="mw-page-title-main">Surveyor program</span> 1960s NASA program to soft-land robotic probes on the Moon

The Surveyor program was a NASA program that, from June 1966 through January 1968, sent seven robotic spacecraft to the surface of the Moon. Its primary goal was to demonstrate the feasibility of soft landings on the Moon. The Surveyor craft were the first American spacecraft to achieve soft landing on an extraterrestrial body. The missions called for the craft to travel directly to the Moon on an impact trajectory, a journey that lasted 63 to 65 hours, and ended with a deceleration of just over three minutes to a soft landing.

<span class="mw-page-title-main">Surveyor 3</span> American lunar lander

Surveyor 3 is the third lander of the American uncrewed Surveyor program sent to explore the surface of the Moon in 1967 and the second to successfully land. It was the first mission to carry a surface-soil sampling-scoop.

<span class="mw-page-title-main">Pioneer 4</span> NASA robotic spacecraft designed to study the Moon

Pioneer 4 was an American spin-stabilized uncrewed spacecraft launched as part of the Pioneer program on a lunar flyby trajectory and into a heliocentric orbit making it the first probe of the United States to escape from the Earth's gravity. Launched on March 3, 1959, it carried a payload similar to Pioneer 3: a lunar radiation environment experiment using a Geiger–Müller tube detector and a lunar photography experiment. It passed within 58,983 km (36,650 mi) of the Moon's surface. However, Pioneer 4 did not come close enough to trigger its photoelectric sensor. The spacecraft was still in solar orbit as of 1969. It was the only successful lunar probe launched by the U.S. in 12 attempts between 1958 and 1963; only in 1964 would Ranger 7 surpass its success by accomplishing all of its mission objectives.

<span class="mw-page-title-main">Ranger 3</span> 1962 robotic lunar exploration mission by NASA; malfunctioned

Ranger 3 was a space exploration mission conducted by NASA to study the Moon. The Ranger 3 robotic spacecraft was launched January 26, 1962 as part of the Ranger program. Due to a series of malfunctions, the spacecraft missed the Moon by 22,000 mi (35,000 km) and entered a heliocentric orbit.

<span class="mw-page-title-main">Ranger 4</span> 1962 American unmanned space flight intended to study the Moon

Ranger 4 was a spacecraft of the Ranger program, launched in 1962. It was designed to transmit pictures of the lunar surface to Earth stations during a period of 10 minutes of flight prior to crashing upon the Moon, to rough-land a seismometer capsule on the Moon, to collect gamma-ray data in flight, to study radar reflectivity of the lunar surface, and to continue testing of the Ranger program for development of lunar and interplanetary spacecraft.

<span class="mw-page-title-main">Ranger 5</span> US unmanned lunar space probe

Ranger 5 was a spacecraft of the Ranger program designed to transmit pictures of the lunar surface to Earth stations during a period of 10 minutes of flight prior to impacting on the Moon, to rough-land a seismometer capsule on the Moon, to collect gamma-ray data in flight, to study radar reflectivity of the lunar surface, and to continue testing of the Ranger program for development of lunar and interplanetary spacecraft. Due to an unknown malfunction, the spacecraft ran out of power and ceased operation. It passed within 725 km of the Moon.

<span class="mw-page-title-main">Surveyor 1</span> Lunar lander spacecraft

Surveyor 1 was the first lunar soft-lander in the uncrewed Surveyor program of the National Aeronautics and Space Administration. This lunar soft-lander gathered data about the lunar surface that would be needed for the crewed Apollo Moon landings that began in 1969. The successful soft landing of Surveyor 1 on the Ocean of Storms was the first by an American space probe on any extraterrestrial body, occurring on the first attempt and just four months after the first soft Moon landing by the Soviet Union's Luna 9 probe.

<span class="mw-page-title-main">Lander (spacecraft)</span> Type of spacecraft

A lander is a spacecraft that descends towards, then comes to rest on the surface of an astronomical body other than Earth. In contrast to an impact probe, which makes a hard landing that damages or destroys the probe upon reaching the surface, a lander makes a soft landing after which the probe remains functional.

<span class="mw-page-title-main">Ranger 7</span> United States lunar space probe

Ranger 7 was the first space probe of the United States to successfully transmit close images of the lunar surface back to Earth. It was also the first completely successful flight of the Ranger program. Launched on July 28, 1964, Ranger 7 was designed to achieve a lunar-impact trajectory and to transmit high-resolution photographs of the lunar surface during the final minutes of flight up to impact.

<span class="mw-page-title-main">Ranger 6</span> United States lunar space probe

Ranger 6 was a lunar probe in the NASA Ranger program, a series of robotic spacecraft of the early and mid-1960s to obtain close-up images of the Moon's surface. It was launched on January 30, 1964 and was designed to transmit high-resolution photographs of the lunar terrain during the final minutes of flight until impacting the surface. The spacecraft carried six television vidicon cameras—two wide-angle and four narrow-angle —to accomplish these objectives. The cameras were arranged in two separate chains, or channels, each self-contained with separate power supplies, timers, and transmitters so as to afford the greatest reliability and probability of obtaining high-quality television pictures. No other experiments were carried on the spacecraft. Due to a failure of the camera system, no images were returned.

<span class="mw-page-title-main">Ranger 8</span> NASA spacecraft to explore the Moon, 1965

Ranger 8 was a lunar probe in the Ranger program, a robotic spacecraft series launched by NASA in the early-to-mid-1960s to obtain the first close-up images of the Moon's surface. These pictures helped select landing sites for Apollo missions and were used for scientific study. During its 1965 mission, Ranger 8 transmitted 7,137 lunar surface photographs before it crashed into the Moon as planned. This was the second successful mission in the Ranger series, following Ranger 7. Ranger 8's design and purpose were very similar to those of Ranger 7. It had six television vidicon cameras: two full-scan and four partial-scan. Its sole purpose was to document the Moon's surface.

<span class="mw-page-title-main">Ranger 9</span> Lunar space probe launched in 1965 as part of NASAs Ranger program

Ranger 9 was a Lunar probe, launched in 1965 by NASA. It was designed to achieve a lunar impact trajectory and to transmit high-resolution photographs of the lunar surface during the final minutes of flight up to impact. The spacecraft carried six television vidicon cameras—two wide-angle and four narrow-angle —to accomplish these objectives. The cameras were arranged in two separate chains, or channels, each self-contained with separate power supplies, timers, and transmitters so as to afford the greatest reliability and probability of obtaining high-quality television pictures. These images were broadcast live on television to millions of viewers across the United States. No other experiments were carried on the spacecraft.

<span class="mw-page-title-main">Moon landing</span> Arrival of a spacecraft on the Moons surface

A Moon landing or lunar landing is the arrival of a spacecraft on the surface of the Moon, including both crewed and robotic missions. The first human-made object to touch the Moon was Luna 2 in 1959.

<span class="mw-page-title-main">GRAIL</span> 2011–12 NASA mission to study the Moons geology

The Gravity Recovery and Interior Laboratory (GRAIL) was an American lunar science mission in NASA's Discovery Program which used high-quality gravitational field mapping of the Moon to determine its interior structure. The two small spacecraft GRAIL A (Ebb) and GRAIL B (Flow) were launched on 10 September 2011 aboard a single launch vehicle: the most-powerful configuration of a Delta II, the 7920H-10. GRAIL A separated from the rocket about nine minutes after launch, GRAIL B followed about eight minutes later. They arrived at their orbits around the Moon 25 hours apart. The first probe entered orbit on 31 December 2011 and the second followed on 1 January 2012. The two spacecraft impacted the Lunar surface on December 17, 2012.

<span class="mw-page-title-main">Exploration of Saturn</span> Overview of the exploration of Saturn

The exploration of Saturn has been solely performed by crewless probes. Three missions were flybys, which formed an extended foundation of knowledge about the system. The Cassini–Huygens spacecraft, launched in 1997, was in orbit from 2004 to 2017.

<span class="mw-page-title-main">Lunar Flashlight</span> Lunar orbiter by NASA

Lunar Flashlight was a low-cost CubeSat lunar orbiter mission to explore, locate, and estimate size and composition of water ice deposits on the Moon for future exploitation by robots or humans.

References

  1. Cortright Oral History (p25)
  2. Dick, Steven J. "NASA's First 50 Years: Historical Perspectives" (PDF). history.nasa.gov. NASA. p. 12. Retrieved 17 June 2019.
  3. Johnston, Louis; Williamson, Samuel H. (2023). "What Was the U.S. GDP Then?". MeasuringWorth. Retrieved November 30, 2023. United States Gross Domestic Product deflator figures follow the Measuring Worth series.
  4. Jet Propulsion Laboratory - Malling, L. R. (1962). Planetary photography- Television camera for a geological survey of the planet Mars (PDF) (Report). NASA-JPL.
  5. Jet Propulsion Laboratory - Malling, L. R. (1963). Space astronomy and the slow-scan vidicon system (PDF) (Report). NASA-JPL.
  6. Jet Propulsion Laboratory - Malling, L. R. (1966). Digital television camera control system Patent (PDF) (Report). NASA-JPL.
  7. Jet Propulsion Laboratory - Malling, L. R. (1968). Reduced bandwidth video communication system utilizing sampling techniques Patent (PDF) (Report). NASA-JPL.
  8. "LUNAR IMPACT: A History of Project Ranger, Part I. The Original Ranger, Chapter Two - ORGANIZING THE CAMPAIGN". NASA History. NASA. Retrieved 14 July 2016.
  9. Nuvistor Valves by Stef Niewiadomski.
  10. "ch8".
  11. "The View From Ranger". NASA-JPL. 1961. p. 47.

Both links lead to a whole book on the program. For the HTML one, scroll down to see the table of contents link.